An engine system includes an engine configured to combust liquid natural gas and generate an exhaust gas comprising methane; a catalytic reactor coupled downstream of the engine and configured to convert methane into a product through one or more of oxidative coupling of methane (OCM) reaction and steam methane reforming (SMR) reaction; and a recirculation loop configured to recirculate at least a part of the product back to the engine.

A method and modular desulfurization-decarbonization apparatus for removing contaminants from exhaust gas is described. The apparatus comprises discrete modular units with distinct functions. The modular units may be housed in standard shipping containers and installed on cargo ships. The modules can be removed and replaced while docking with minimal disruption to ship and port operations.

An exhaust conduit for a marine exhaust system includes an inlet end portion connectable to an exhaust manifold, an outlet end portion that directs exhaust gases toward an exhaust system outlet, a catalytic converter assembly arranged between the inlet and outlet end portions, and inner and outer tubes. The inner tube directs exhaust gases from the exhaust manifold to the catalytic converter assembly, and the outer tube surrounds the inner tube to define a cooling liquid passage between the inner and outer tubes. A flange is secured to the inner and outer tubes at inlet ends thereof, the flange being connectable to an outlet of the exhaust manifold. The inner tube has a uniform diameter between the flange and the catalytic converter assembly, and is welded to the flange independently of the outer tube. First and second welds join the inner and outer tubes to the flange at radially inner and outer faces, respectively, of a flange rim.

A system for treating engine exhaust gas, which engine exhaust gas has a temperature of between T1 and T2, comprises a SCR reactor for converting NOx in a medium containing the engine exhaust gas into N2 and H2O. The SCR reactor has an inlet for receiving the medium and an outlet for outputting the NOx reduced medium. A first boiler unit has an outlet for outputting boiler exhaust gas (temperature greater than T3, T3>T1) from the first boiler unit. A mixing unit mixes the engine exhaust gas with the boiler exhaust gas to produce the medium. The mixing unit has a first inlet communicating with the engine for receiving the engine exhaust gas, a second inlet communicating with the outlet of the first boiler unit for receiving the boiler exhaust gas and an outlet for outputting the medium. The mixing unit outlet communicates with the inlet of the SCR reactor.

A reaction device of a marine SCR system comprises a conveying unit (110), a reaction chamber (120), at least one catalyst module (130), and an air homogenization chamber (140), wherein, the conveying unit (110) includes an input pipeline (111) and an output pipeline (112) sleeved outside the input pipeline (111). One end of the reaction chamber (120) is connected to the conveying unit (110). The reaction chamber (120) comprises an inner cylinder (121) and an outer cylinder (122) sleeved outside the inner cylinder (121), the inner cylinder (121) is in communication with the input pipeline (111), and the outer cylinder (122) is in communication with the output pipeline (112). The catalyst module (130) is provided between the inner cylinder (121) and the outer cylinder (122). The air homogenization chamber (140) is connected to the other end of the reaction chamber (120) and is in communication with both the inner cylinder (121) and the outer cylinder (122). With the reaction device of the marine SCR system whereby the outer cylinder is sleeved outside the inner cylinder, flue gas from the inner cylinder is turned by the air homogenization chamber and then flows back into the outer cylinder. This can not only substantially reduce the size of the reaction device to improve the integration of the SCR system, but also allow the flue gas to turn in the air homogenization chamber and then flow back, so that the flue gas and a reducing agent can be fully mixed in the air homogenization chamber to improve the catalytic reaction efficiency.

A jet propelled watercraft includes a first exhaust pipe connected to an exhaust port, a catalyst storage connected to the first exhaust pipe, a second exhaust pipe connected to the catalyst storage, and a water lock connected to the second exhaust pipe. The catalyst storage and the water lock are located outward in a width direction with respect to the exhaust port of the engine in a plan view of the jet propelled watercraft.

A system, a use of such a system and a multi system for cleaning exhaust gas from a combustion engine. The system comprises a first exhaust gas scrubber to communicate with a scrubber water circulation tank. A first outlet of the first exhaust gas scrubber is connectable to a first inlet of the scrubber water circulation tank, and a first inlet of the first exhaust gas scrubber is connectable to a first outlet of the scrubber water circulation tank, to enable circulation of scrubber water between the scrubber water circulation tank and the first exhaust gas scrubber. An air supply device feeds air into the first exhaust gas scrubber to aerate the scrubber water during its passage through the first exhaust gas scrubber. Accordingly, a second inlet of the first exhaust gas scrubber is arranged to be connected to an outlet of the air supply device.

The present invention relates to an apparatus for reducing greenhouse gas emission in a vessel, and a vessel including the same, which are capable of satisfying IMO greenhouse gas emission regulations by separating and discharging NO.sub.x, SO.sub.x, and CO.sub.2 from exhaust gas exhausted from a vessel engine and increasing CO.sub.2 solubility and CO.sub.2 removal efficiency by removing CO.sub.2 after removing SO.sub.x.

To provide a reducer supply device that can be made compact and has excellent maintainability. The reducer supply device includes a nozzle unit that adjusts a flow rate of a reducer which is to be supplied to a NOx purification catalyst device; and a pump unit that supplies the reducer to the nozzle unit. The nozzle unit and the pump unit are arranged at positions offset from each other in top view.

A prechamber assembly includes a cylinder head including a coolant cavity, a prechamber body located within the cylinder head, the prechamber body including a nozzle, and an annular sleeve radially surrounding a portion of the prechamber body. The sleeve includes a plurality of coolant inlet holes. A portion of the prechamber body is radially spaced from the sleeve to form a coolant sleeve annulus extending along a length of the prechamber body above the coolant inlet holes. The coolant cavity and the coolant sleeve annulus are in fluid communication through the plurality of coolant inlet holes.